Apparatus and method for UV wastewater purification in septic tank systems

Abstract

The apparatus for UV wastewater purification in septic tank systems has an ozone free ultraviolet lamp disposed in PVC piping buried in the ground and located between the septic tank and the drainfield. The PVC piping includes a water inlet and an outlet connected by a U-shaped section of piping. The UV lamp is housed in a quartz tube, or in an alternative embodiment, in a Teflon tube, and placed in a cylindrical insert having a plurality of ports defined in the walls of the cylinder. The insert is placed in a vertically oriented leg of the U-shaped piping at the water outlet, the wastewater flowing through the insert parallel to the ultraviolet lamp. Access to the UV lamp for maintenance is provided by a vertically oriented riser pipe buried in the ground and having a length corresponding to the desired depth of the apparatus, the riser housing the electrical wiring and having a cap at ground level. The method for UV wastewater purification in septic tank systems includes the steps of selecting an ozone free UV lamp, disposing the lamp in a cylindrical insert having a plurality of ports, and placing the insert in PVC piping buried in the ground between the septic tank and the drainfield.

We claim:  
     
       1. An apparatus for UV wastewater purification in a septic tank system having a septic tank and a drainfield, the apparatus being adapted for placement underground between a septic tank end of the septic tank system and a drainfield end of the septic tank system, the apparatus comprising: 
       a) a system of polyvinyl chloride piping including a vertically ascending pipe, and a vertically oriented riser pipe accessible from above the ground, said system forming a continuous fluid conduit, the wastewater flowing through said system of piping between the septic tank and the drainfield;  
       b) an ultraviolet lamp emitting ozone free ultraviolet radiation in a wavelength range having a bactericidal effect, the lamp including a power cord adapted for connection to a power supply, the ultraviolet lamp being disposed within said system of PVC piping;  
       c) a cap attached to said riser pipe for providing a waterproof cover for the riser pipe; and  
       d) an insert, said ultraviolet lamp being housed in the insert, the insert having a plurality of ports for the ingress and outflow of wastewater, the insert being disposed in the vertically ascending pipe of said system of piping.  
     
     
       2. The apparatus for wastewater purification according to claim  1 , further comprising a protective tube, said ultraviolet lamp being placed in the protective tube, the protective tube being adapted for protecting said ultraviolet lamp from contamination by wastewater. 
     
     
       3. The apparatus for wastewater purification according to claim  2 , wherein said protective tube is made from quartz crystal. 
     
     
       4. The apparatus for wastewater purification according to claim  2 , wherein said protective tube is made from transparent Teflon. 
     
     
       5. The apparatus for wastewater purification according to claim  2 , wherein said insert further comprises a flow restrictor disposed about said protective tube at about the center of the longitudinal axis of said insert, said flow restrictor being an annular disk having a plurality of orifices defined therein. 
     
     
       6. The apparatus for wastewater purification according to claim  1 , wherein said system of polyvinyl chloride piping comprises: 
       a) an inlet tube adapted for connection to the septic tank end of the septic tank system;  
       b) an outlet tube adapted for connection to the drainfield end of the septic tank system;  
       c) a U-shaped section disposed between said inlet tube and said outlet tube, including the vertically ascending pipe being positioned below the outlet tube; and  
       d) wherein the riser pipe is disposed between said outlet tube and the ground, an end of the riser tube being level with the surface of the ground.  
     
     
       7. The apparatus for wastewater purification according to claim  1 , wherein said ultraviolet lamp further includes a transformer plug having an LED indicator for indicating when power is applied to said ultraviolet light, and wherein said cap includes a waterproof viewing port for observing the LED indicator from above ground with said cap in place on the riser pipe. 
     
     
       8. The apparatus for wastewater purification according to claim  1 , wherein said ultraviolet lamp emits radiation having a wavelength between about 150 to 300 nanometers. 
     
     
       9. A method for UV wastewater purification in a septic tank system having a septic tank and a drainfield comprising the steps of: 
       (a) selecting an ultraviolet lamp providing ozone free radiation at a wavelength having bactericidal effect;  
       (b) constructing a system of PVC piping with waterproof joints having an inlet joined to an outlet by a U-shaped section and a riser pipe connected to the outlet fitting;  
       (c) disposing the system of PVC piping underground with the inlet connected to the septic tank end of the system and the outlet connected to the drainfield end of the system;  
       (d) placing the ultraviolet lamp into a protective tube in an insert having a plurality of ports for the flow of effluent parallel to the ultraviolet lamp;  
       (e) lowering the insert through the riser pipe into a leg of the U-shaped section;  
       (f) cutting the riser pipe so that the top of the riser is level with the surface of the ground;  
       (g) connecting the ultraviolet lamp to a source of electrical power; and  
       (h) covering the riser pipe with a cap.  
     
     
       10. The method for UV wastewater purification according to claim  9 , wherein the step of disposing the system of PVC pipe underground further comprises burying the system of PVC pipe directly in the ground. 
         11 .The method for UV wastewater purification according to claim  9 , wherein the step of disposing the system of PVC pipe underground further comprises disposing the system of PVC pipe in a pump tank reservoir. 
     
     
       12. The method for UV wastewater purification according to claim  9 , wherein the step of connecting the ultraviolet lamp to a source of electrical power further comprises connecting the lamp to an above ground ballast and junction box. 
     
     
       13. The method for UV wastewater purification according to claim  9 , wherein the step of connecting the ultraviolet lamp to a source of electrical power further comprises: 
       (a) installing a weatherproof receptacle in a weather tight electrical box fixedly attached to the bottom surface of a cap adapted for waterproof covering of the riser;  
       (b) connecting a power source to the water tight electrical box;  
       (c) plugging the ultraviolet light into the receptacle; and  
       (d) thereafter performing said step of covering the riser pipe with the cap.  
     
     
       14. An apparatus for UV wastewater purification in a septic tank system having a septic tank and a drainfield, the apparatus being adapted for burial in the ground between a septic tank end of the septic tank system and a drainfield end of the septic tank system, the apparatus comprising: 
       a) a system of polyvinyl chloride piping including a vertically ascending pipe and a vertically oriented riser pipe accessible from above the ground, the wastewater flowing through said system of piping between the septic tank and the drainfield;  
       b) an ultraviolet lamp emitting ozone free ultraviolet radiation in a wavelength range having a bactericidal effect, the lamp including a power cord adapted for connection to a power supply;  
       c) a protective tube, said ultraviolet lamp being placed in the protective tube, the protective tube being adapted for protecting said ultraviolet lamp from contamination by wastewater;  
       d) an insert for housing said ultraviolet lamp and said protective tube, the insert having a plurality of ports for the ingress and outflow of wastewater, the insert being disposed in the vertically ascending pipe of said system of piping; and  
       e) a cap for providing a waterproof cover for the riser pipe, the cap including an electrical receptacle adapted for connection to a power supply.  
     
     
       15. The apparatus for wastewater purification according to claim  14 , wherein said protective tube is made from quartz crystal. 
     
     
       16. The apparatus for wastewater purification according to claim  14 , wherein said protective tube is made from transparent Teflon. 
     
     
       17. The apparatus for wastewater purification according to claim  14 , wherein said system of polyvinyl chloride piping comprises: 
       a) an inlet tube adapted for connection to the septic tank end of the septic tank system;  
       b) an outlet tube adapted for connection to the drainfield end of the septic tank system;  
       c) a U-shaped section disposed between said inlet tube and said outlet tube, including the vertically ascending pipe being positioned below the outlet tube; and  
       d) wherein the riser pipe is adapted to be disposed between said outlet tube and the ground, an end of the riser tube being level with the surface of the ground.